Resveratrol supplementation reduces oxidative stress and modulates the immune response in free-living animals during a viral infection
Résumé
1. Diet quality may have an important effect on the regulation of oxidative status
and the immune system during an infectious disease. However, the relationship
among intake of specific dietary molecules, an individual’s oxidative status and the
occurrence and progress of a viral disease remains almost unexplored in free‐living
organisms.
2. Here, we study a wild, long‐lived animal, the Magnificent frigatebird Fregata magnificens
to investigate: (a) the differences in a number of physiological traits (biomarkers
of blood oxidative status, corticosterone (CORT), immunity and
inflammation) between sick and healthy nestlings; and (b) whether experimentally
increased intake of resveratrol (a polyphenol with antioxidant and antiviral properties)
affects these physiological markers during the progress of a severe viral
disease.
3. Birds with visible clinical signs showed higher oxidative damage, haemolysis and
haemagglutination scores and lower antioxidant defences in comparison with
birds without clinical signs. At the end of the experiment, supplemented birds
showed the following: (a) increased plasma haptoglobin levels and circulating antioxidant
defences; (b) reduced generation of lipid oxidative damage; and (c) negligible
to no influence on immune markers, baseline CORT levels and activity of
antioxidant enzymes.
4. Our work illustrates how the availability of specific organic molecules in the diet
may constrain the individuals’ capacity to cope with viral infections in free‐living
animals